Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04J—MULTIPLEX COMMUNICATION
  • H04J11/00—Orthogonal multiplex systems, e.g. using WALSH codes
  • H04J11/0023—Interference mitigation or co-ordination
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/003—Arrangements for allocating sub-channels of the transmission path
  • H04L5/0053—Allocation of signalling, i.e. of overhead other than pilot signals
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W72/00—Local resource management
  • H04W72/20—Control channels or signalling for resource management
  • H04W72/23—Control channels or signalling for resource management in the downlink direction of a wireless link, i.e. towards a terminal
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/003—Arrangements for allocating sub-channels of the transmission path
  • H04L5/0058—Allocation criteria
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04J—MULTIPLEX COMMUNICATION
  • H04J2211/00—Orthogonal indexing scheme relating to orthogonal multiplex systems
  • H04J2211/003—Orthogonal indexing scheme relating to orthogonal multiplex systems within particular systems or standards
  • H04J2211/005—Long term evolution [LTE]
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L5/00—Arrangements affording multiple use of the transmission path
  • H04L5/0001—Arrangements for dividing the transmission path
  • H04L5/0003—Two-dimensional division
  • H04L5/0005—Time-frequency
  • H04L5/0007—Time-frequency the frequencies being orthogonal, e.g. OFDM(A) or DMT

Definitions

• the present invention relates to a wireless communication technology, and more particularly to a resource mapping method and apparatus for a downlink control channel in an LTE (Long Term Evolution) / LTE-A (LTE-Advanced, Enhanced Long Term Evolution) system.
• LTE Long Term Evolution
• LTE-A Long Term Evolution-Advanced, Enhanced Long Term Evolution
• the downlink control information (DCI, Downlink Control Information) is transmitted by the base station in the form of a Physical Downlink Control Channel (PDCCH), and the data is shared by the base station by the physical downlink shared channel (PDSCH, Physical Downlink Shared). Channel) Send in form.
• the PDCCH and the PDSCH appear in each subframe in a time-division manner.
• the PDCCH supports spatial diversity multi-antenna transmission based on Cell-specific Reference Signal (CRS), and the maximum number of transmitting antennas is 4.
• the PDCCH region is further divided into a common search space and a user-specific (UE-specific) search space. All users (UE, User Equipment) have the same common search space, and all users search for their own PDCCH in the same space.
• the user-specific search space is related to the user's RNTI (Radio Network Temporary Identifier), and the user searches for his own PDCCH only in his own space.
• RNTI Radio Network Temporary Identifier
• the downlink can support up to eight transmit antennas to achieve IGbps transmission rates.
• the PDSCH not only increases the transmission rate, but also expands the signal coverage.
• the PDCCH does not support 8-antenna transmission, and only supports transmission diversity of up to 4 antennas, so the same beamforming gain as the PDSCH cannot be obtained.
• the multi-point cooperative transmission technology based on the network architecture of multiple geographically separated RRHs (Remote Radio Heads) will be widely used in future wireless communication systems.
• the cell capacity is increased by simultaneously scheduling the PDSCH of users in the coverage of each RRH to obtain the cell splitting gain.
• the cell capacity can also be improved by means of PDSCH spatial multiplexing of multiple users.
• the existing CRS-based PDCCH cannot obtain the cell splitting gain. Therefore, people pay attention to the research of PDCCH based on DM-RS (De Modulation Reference Symbol), that is, the PDCCH from the traditional first N OFDM symbols. Expand to the PDSCH region starting from the N+1th symbol, as shown in Figure 2.
• DM-RS Demo Modulation Reference Symbol
• the user can obtain the specific location of the new PDCCH region by using signaling, that is, the subcarrier resources occupied in the frequency domain and/or the information of the OFDM symbols occupied in the time domain, and the user can perform blind detection in this region to correctly
• the respective PDCCHs are demodulated.
• An object of the embodiments of the present invention is to provide a resource mapping method and apparatus for a downlink control channel, so that the number of PDCCH resources of each user is uniformized, thereby ensuring that the performance of the PDCCH is not affected by the pilot signal. influences.
• a resource mapping method for a downlink control channel includes:
• PDCCH downlink control channel
• a base station configured to perform resource mapping of a downlink control channel, where the base station includes:
• a first determining unit configured to determine, according to a size of a resource sub-block in a resource block (RB), a number of resource sub-blocks corresponding to a predetermined number of enhanced control channel elements (eCCEs);
• a second determining unit configured to determine, according to the number of resource sub-blocks corresponding to the predetermined number of eCCEs, the number of RBs to which the predetermined number of eCCEs need to be mapped;
• mapping unit which maps an eCCE of a downlink control channel (PDCCH) to an RB according to the number of RBs to which the predetermined number of eCCEs need to be mapped, where the eCCE in the PDCCH or a resource corresponding to a predetermined number of eCCEs
• the sub-blocks have different positions on the respective RBs.
• a computer readable program wherein, when the program is executed in a base station, the program causes a computer to perform the aforementioned resource mapping method of the downlink control channel in the base station.
• a storage medium storing a computer readable program
• the computer readable program causes a computer to perform a resource mapping method of the aforementioned downlink control channel in a base station.
• An advantageous effect of the embodiment of the present invention is that the PDCCH resources of each user are equalized by alternately changing the mapping order of the PDCCHs of the respective users in the resource blocks, thereby ensuring that the performance of the PDCCH is not affected by the pilot.
• the effect of the signal is that the PDCCH resources of each user are equalized by alternately changing the mapping order of the PDCCHs of the respective users in the resource blocks, thereby ensuring that the performance of the PDCCH is not affected by the pilot. The effect of the signal.
• FIG. 1 is a schematic diagram of a PDCCH and PDSCH transmission area in an LTE system
• FIG. 2 is a schematic diagram of a new PDCCH and PDSCH transmission area
• FIG. 3 is a schematic diagram of a pilot signal position of a transmission region of a new PDCCH
• FIG. 4 is a schematic diagram of a transmission location of a new PDCCH of multiple users
• FIG. 5 is a flowchart of a resource mapping method of a downlink control channel according to an embodiment of the present invention.
• FIG. 6 is a schematic diagram of resource mapping according to an embodiment of the present invention.
• FIG. 7 is a schematic diagram of resource mapping according to another embodiment of the present invention.
• FIG. 8 is a schematic diagram of resource mapping according to another embodiment of the present invention.
• FIG. 9 is a schematic diagram of resource mapping according to another embodiment of the present invention.
• FIG. 10 is a schematic structural diagram of a base station according to an embodiment of the present invention. detailed description
• the resource mapping of the new PDCCH can be divided into two categories: one is continuous resource mapping, that is, multiple CCEs of one candidate of the PDCCH are mapped to adjacent time-frequency resources.
• one is continuous resource mapping, that is, multiple CCEs of one candidate of the PDCCH are mapped to adjacent time-frequency resources.
• the base station can send a PDCCH to the user on the time-frequency resource with better channel quality based on the channel information fed back by the user or the channel information measured by the base station to obtain the frequency selection scheduling gain.
• the other type is a discrete resource mapping, that is, multiple CCEs of one candidate of the PDCCH are mapped to non-adjacent time-frequency resources. Through this mapping, the base station can obtain the frequency domain diversity gain when the channel information cannot be obtained, so as to ensure the performance of the PDCCH.
• the PDCCHs of multiple users need to be mapped to different subcarriers of the same resource block, that is, the PDCCHs of multiple users are multiplexed by FDM (Frequency-Division Multiplexing).
• the PDCCH of each user occupies M subcarriers, which is called an enhanced control channel unit (eCCE), as shown in FIG. 3 and FIG. 4.
• eCCE enhanced control channel unit
• 3 is a schematic diagram of possible resource locations of a new PDCCH on one RB
• FIG. 4 is a schematic diagram of possible resource locations of a new PDCCH of multiple users on one RB.
• the location of the pilot signal needs to be reserved in the new PDCCH mapping, thus causing the PDCCH resource to change as the pilot signal overhead changes.
• a cell common pilot such as CRS
• a demodulation pilot such as DM-RS
• the embodiment of the present invention provides a method and apparatus for resource mapping of a downlink control channel, which alternately changes the mapping order of new PDCCHs of each user in each resource block (Resource Block, RB), so that each The number of resources of the user's new PDCCH is equalized, thereby ensuring that the performance of the new PDCCH is not affected by the pilot signal.
• Resource Block Resource Block
• Example 1 The embodiment of the invention provides a resource mapping method for a downlink control channel.
• Figure 5 is a flow chart of the method. Referring to Figure 5, the method includes:
• Step 501 Determine, according to a size of a resource sub-block in a resource block (RB), a number of resource sub-blocks corresponding to a predetermined number of enhanced control channel elements (eCCEs);
• eCCEs enhanced control channel elements
• Each RB is divided into a plurality of smaller resource sub-blocks as needed. For example, if four users' PDCCHs are multiplexed by one RB, one RB may be divided into four smaller resource sub-blocks. This embodiment does not limit the specific division strategy and division method.
• the number of resource sub-blocks corresponding to one eCCE can be determined according to the size of each resource sub-block.
• the correspondence between the two is determined by using multiple eCCEs corresponding to the integer number of resource sub-blocks. For example, if an eCCE corresponds to 1.5 resource sub-blocks, it is determined that 2 eCCEs correspond to 3 resource sub-blocks.
• Step 502 Determine, according to the number of resource sub-blocks that are required by the predetermined number of eCCEs, the number of RBs to which the predetermined number of eCCEs need to be mapped;
• the number of corresponding resource sub-blocks required by the predetermined number of eCCEs is the same as the number of RBs that need to be mapped, for example, if one eCCE corresponds to two resource sub-blocks, then one The eCCE needs to be mapped to two RBs, that is, two resource sub-blocks corresponding to one eCCE are located on two RBs.
• the number of RBs that the predetermined number of eCCEs need to be mapped may be determined according to the resource configuration. For example, if one eCCE corresponds to three resource sub-blocks, an eCCE may also be used according to resource configuration. It is mapped to two RBs, that is, three resource sub-blocks corresponding to one eCCE are located on two RBs.
• Step 503 The eCCE of the downlink control channel (PDCCH) is mapped to the RB according to the number of the RBs to be mapped to the predetermined number of eCCEs, where the eCCE in the PDCCH or the resource sub-corresponding to the predetermined number of eCCEs The positions of the blocks on the respective RBs are different.
• PDCCH downlink control channel
• one or more eCCEs of the PDCCH may be mapped to corresponding numbers according to the number of RBs to which the predetermined number of eCCEs need to be mapped.
• the block is mapped to two RBs, and each RB has a resource sub-block corresponding to the eCCE.
• one PDCCH includes two eCCEs, and the four resources corresponding to the two eCCEs of the PDCCH are used.
• the sub-blocks are mapped to 4 RBs, and each RB has a resource sub-block corresponding to the eCCE. And so on, no longer repeat them.
• the eCCEs in the PDCCH or the resource subblocks corresponding to the predetermined number of eCCEs have different locations on the respective RBs.
• the location of the first resource sub-block corresponding to the eCCE on the first RB is corresponding to the eCCE.
• the second resource sub-block has a different location on the second RB.
• the location of the eCCE in the PDCCH or the resource sub-block corresponding to the predetermined number of eCCEs on each RB is periodically cyclically moved. In another embodiment, the location of the eCCE in the PDCCH or the resource sub-block corresponding to the predetermined number of eCCEs on each RB is preset.
• the cyclic manner of the periodic cyclic movement may be determined according to the size of the eCCE or the overhead of the pilot signal in the RB or the size of the aggregation level, or the preset position may be determined.
• the size of the eCCE is one eCCE corresponding to several resource sub-blocks; the size of the aggregation level is also the size of the aggregation level, which determines that one PDCCH contains several eCCEs, and then determines that one PDCCH needs to be mapped to several RBs. The following will be explained by specific examples.
• the cyclic manner of the periodic cyclic movement may also be determined according to a predetermined policy, or the preset position may be determined, that is, no longer varies with the size of the eCCE or the size of the aggregation level.
• the cyclic mode of the periodic cyclic movement or the preset position is set to be fixed.
• the number of resources occupied by each PDCCH is equal or substantially equal, as long as the resource sub-blocks corresponding to the eCCEs of the PDCCH are in different positions on the respective RBs.
• the positions of the resource sub-blocks corresponding to the predetermined number of eCCEs in the PDCCH in the PDCCH are periodically cyclically moved. For example, if one eCCE corresponds to two resource sub-blocks and needs to be mapped to two RBs, if the location of the first resource sub-block corresponding to the eCCE on the first RB is the 2i-1 resource sub-block, The position of the second resource sub-block corresponding to the eCCE on the second RB is the 2ith resource sub-block, where i is a natural number greater than 0.
• the position of the resource sub-block corresponding to the eCCE in the PDCCH on each RB is periodically cyclically moved.
• the location is the 4th-2th resource sub-block
• the location of the third resource sub-block corresponding to the eCCE is the 4i-1th resource sub-block on the third RB
• the fourth resource corresponding to the eCCE The position of the sub-block on the fourth RB is the 4th resource sub-block, where i is a natural number greater than zero. That is, the position of each resource sub-block corresponding to the eCCE on each RB is a relationship of sequential rotational displacement.
• the location of the resource sub-block corresponding to the predetermined number of eCCEs in the PDCCH on each RB is preset. For example, if one eCCE corresponds to three resource sub-blocks and needs to be mapped to three RBs, the position of each resource sub-block corresponding to the eCCE on the RB may be preset. Similarly, in the case where the number of eCCEs of the PDCCH is greater than the predetermined number, the mapping manner may be repeated by using the number of RBs corresponding to the predetermined number as one cycle, or the location of each resource sub-block on the RB may be preset.
• the number of resources occupied by each PDCCH is equal or substantially equal, that is, the number of REs occupied by each PDCCH is substantially equal, that is, the number of REs occupied by each PDCCH is approximately equal, thereby ensuring that the number of REs occupied by each user's PDCCH is substantially equal.
• the performance of the PDCCH is not affected by the pilot signal.
• FIG. 6 is a schematic diagram of PDCCH resource mapping according to an embodiment of the present invention.
• each unit contains 3 subcarriers.
• the size of the unit it is determined that one eCCE needs to correspond to two units, and is mapped into two RBs respectively.
• the mapping relationship between the eCCEs of the four users and the time-frequency resources is: If the user j is mapped to the first RB In the 2i-1th unit, the user j is mapped to the 2ith unit of the second RB. That is, the 2i-1th unit and the 2ith unit are exchanged with each other in a period of 2 RBs. Where i is a natural number greater than zero.
• the PDCCHs of the user 1 and the user 2 are exchanged between unit 1 and unit 2 of different RBs, and the PDCCHs of the user 3 and the user 4 are interchanged between unit 3 and unit 4 of different RBs as an example, but The embodiment is not limited thereto. Regardless of how the mapping is performed, it is only required to ensure that the number of resources occupied by the PDCCH of each user is substantially equal.
• the PDCCH of the user 1 may occupy the unit1 of the first RB and the unit 4 of the second RB
• the PDCCH of the user 2 occupies the unit 2 of the first RB and the unit 3 of the second RB
• the PDCCH of the user 3 occupies the first PDCCH.
• the unit 3 of the RB and the unit 2 of the second RB, the PDCCH of the user 4 occupies the unit 4 of the first RB and the unit 1 of the second RB.
• the PDCCH of the user 3 occupies the unit 3 of the first RB and the unit 4 of the second RB,
• FIG. 7 is a schematic diagram of PDCCH resource mapping according to another embodiment of the present invention.
• each unit contains two sub-carriers.
• the size of the unit it is determined that one eCCE needs to correspond to three units, and is mapped to three respectively.
• the PDCCH of each user includes one eCCE, and the mapping relationship between the eCCEs of the six users and the time-frequency resources is:
• the PDCCH of the user 1 occupies the first RB.
• PDCCH of user 2 occupies unit2 of the first RB, unitl of the second RB and the third RB
• PDCCH of user 3 occupies the first RB Unit2 of the second RB, unit2 of the third RB
• PDCCH of user 4 occupies unit4 of the first RB, unit5 of the second RB, unit6 of the third RB
• PDCCH of user 5 occupies the first RB Unit5, unit6 of the second RB, unit4 of the third RB
• PDCCH of user 6 occupies unit6 of the first RB, unit4 of the second RB, and unit5 of the third RB. It can be seen that the number of resources occupied by each user's PDCCH is 52.
• the embodiment does not limit the specific cyclic mode or the mapping pattern, as long as the number of resources occupied by the PDCCH of each user is equal or substantially equal. For example, if the three units corresponding to one eCCE are mapped to two RBs respectively, the number of resources occupied by the PDCCH of each user may not be the same, but this dynamic resource mapping method is adopted. Fixing the PDCCH of each user to a certain fixed position of the RB still greatly improves the performance of the PDCCH.
• the resource mapping manner of the PDCCH shown in FIG. 7 is equal to the number of allocated resources of each user's PDCCH, which ensures that the performance of the PDCCH is not affected by the pilot signal.
• FIG. 8 is a schematic diagram of PDCCH resource mapping according to another embodiment of the present invention.
• each unit contains four sub-carriers.
• the size of the unit it is determined that one eCCE needs to correspond to 1.5 units, and the two eCCEs correspond to three units, and are respectively mapped into three RBs.
• the pilot signal it is assumed that the DM-RS is a rank that can support the rank and the rank is 4, and the CRS is a supportable antenna.
• the mapping relationship between the eCCEs of the three users and the time-frequency resources is:
• the i-th unit of the first RB is mapped to the mod (i+1, 3) units in the second RB, and to the mod (i+2, 3) units in the third RB.
• i is a natural number greater than zero.
• the PDCCH of the user 1 occupies the unit1 of the first RB, the unit 2 of the second RB, and the unit 3 of the third RB; the PDCCH of the user 2 occupies the unit 2 of the first RB, and the unit 3 of the second RB
• the embodiment does not limit the specific cyclic mode or the mapping pattern, as long as the number of resources occupied by the PDCCH of each user is equal or substantially equal.
• the resource mapping mode of the PDCCH shown in FIG. 8 is that the number of resources allocated to each user's PDCCH is also equal, which ensures that the performance of the PDCCH is not affected by the pilot signal.
• FIG. 9 is a schematic diagram of PDCCH resource mapping according to another embodiment of the present invention.
• two users are multiplexed with one RB as an example.
• An RB is divided into two smaller resource sub-blocks, numbered as unit 1 ⁇ 2, and each unit contains six sub-carriers.
• the size of the unit it is determined that one eCCE needs to correspond to one unit, because it needs to be mapped to different RBs, so two eCCEs are corresponding to two units, and are respectively mapped into two RBs as an example.
• the mapping relationship between the eCCEs of the two users and the time-frequency resources is: if the PDCCH is mapped to the first RB For the i-th unit, the second RB is mapped to the mod(i+1, 2) unit, and i is a natural number greater than zero.
• the PDCCH of the user 1 occupies the unit1 of the first RB and the unit 2 of the second RB; the PDCCH of the user 2 occupies the unit 2 of the first RB and the unit1 of the second RB. It can be seen that the number of resources occupied by each user's PDCCH is 100.
• the number of RBs corresponding to one PDCCH is greater than 2
• the above alternate manner may be repeated, that is, 2 RBs are one cycle, and 2 Alternate mapping within RB.
• the embodiment does not limit the specific cyclic mode or the mapping pattern, as long as the number of resources occupied by the PDCCH of each user is equal or substantially equal.
• the number of resources allocated to each user's PDCCH is also equal, which ensures that the performance of the PDCCH is not affected by the pilot signal.
• the present invention further provides a base station, which is similar to the resource mapping method of the downlink control channel of the first embodiment, and the specific implementation of the method is as described in the following Embodiment 2. Embodiments of the method, the same points will not be described again.
• the embodiment of the invention provides a base station, where the base station user performs resource mapping of a downlink control channel.
• the base station includes:
• a first determining unit 101 which determines, according to a size of a resource sub-block in one resource block (RB), a number of resource sub-blocks corresponding to a predetermined number of enhanced control channel units (eCCEs);
• a second determining unit 102 which determines, according to the number of resource sub-blocks that are required by the predetermined number of eCCEs, the number of RBs to which the predetermined number of eCCEs need to be mapped;
• mapping unit 103 which maps an eCCE of a downlink control channel (PDCCH) to a corresponding number of RBs according to the number of RBs to which the predetermined number of eCCEs need to be mapped, where the eCCE in the PDCCH or a predetermined number of
• the resource sub-blocks corresponding to the eCCE have different locations on the respective RBs.
• the location of the eCCE in the PDCCH or the resource sub-block corresponding to the predetermined number of eCCEs on each RB is periodically cyclically moved.
• the location of the eCCE in the PDCCH or the resource sub-block corresponding to the predetermined number of eCCEs on each RB is preset.
• the mapping unit 103 further determines a cyclic manner of the periodic cyclic movement according to the size of the eCCE or the overhead of the pilot symbol in the RB or the size of the aggregation level, or determines the foregoing
• the set position is such that the number of resources occupied by each PDCCH is equal or substantially equal.
• the mapping unit 103 further determines a cyclic manner of the periodic cyclic movement according to a predetermined policy, or determines the preset position such that the number of resources occupied by each PDCCH is equal or substantially equal.
• the embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a base station, the program causes the computer to perform the resource mapping method of the downlink control channel described in Embodiment 1 in the base station.
• the embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes the computer to perform the resource mapping method of the downlink control channel described in Embodiment 1 in the base station.
• the above apparatus and method of the present invention may be implemented by hardware, or may be implemented by hardware in combination with software.
• the present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps.
• Logic components such as field programmable logic components, microprocessors, processors used in computers, and the like.
• the present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, or the like.

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